Feeding mechanism for sewing-machines.



A. GRIEB.

FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED DEC. 12. 1913.

1,243,160, Patented Oct. 16,1917.

2 SHEETSSHEET I.

WITNESSES:

WW4 70' 4 /Zwa A. GRIEB.

FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED DEC-I2. I9I3.

Patented Oct. 16, 1917.

2 SHEETSSHEET 2 WI T/VESSES:

kw-Mild 7W ax 214 ALFRED GRIEB,

sra'rns 70F ELIZABETH, nnw zrnnsny, n'ssrenon 7T0 TI-IE SINGER MANUFAC- TURING('c0MPAnY-, A CQBPOBJATIQNJOHENEW JERSEY r 'rnn nnie Eon sewmamd mes.

To all whom it may concern: 'Be it known that I, ALFRED GRIEB, a citizen of the United-States, r'esidingat Elizabeth, in the county of -Union and;State of New Jersey, have invented "certain new and useful Improvements in Feeding Mechanisms for Sewing-Machinedbf'which the following is a specification, reference being had therein to'the accompanyingdrawings. .T his inventioirrelates to improvements 'in feeding mechanisms for sewing machines, and has for its object'to improve thatfclass of overseaming sewing machines forming the subject of my Patent No; 932,272,. of ,August 24:, 1909.

In its preferredform the machine is provided with a reciprocating needle, two loopers or thread-carriers by which a two-"or three-thread oversea m i s produced, and 0pposed feed-dogs which grip the? work between their faces'during feeding movements imparted simultaneously to each dog. Operative movements are imparted "to the aforesaid members from a single shaft journaled below theworlrplate of the'ma hine.

The lower feed-dog is carried by a feedbar to which reciprocatory movements are imparted from a rocker actuate'dby an eccentric on the driving shaft and'provided with a lateral arm connected to the rearend of a link-bar which serves'to transmit reciprocatory movements to the upper feeddog, said dog being supported by a swinging carrier pivotally'mount'ed upon one arm of a bellcrank.' Th'e bell-crank is fulcrumed upon a rocking presser lever pivotally supported uponthe sewing machine frame, and'its' second arm is'conn ected to aneccentric-rod'having a strap which embraces an eccentr c onthe drivlng shaft, by which rocking movements are impartedto the bell cr.ank: to alternately raise and lower the upperfeed-dogh lhe bell crank'is so arranged with respect to its actuating eccentric and to the presser-lever that its continued movement after lowering (the feeddog carrier to clamp the upper feed-dog upon the work, is upon said carrier as a fulcrum, whereby the 'presser-lever is rocked and the presser foot lifted above the work. othenwor'd's," the lifting bellcrank for the upper feed-dog is provided with two. fulcrum points, fir st a pivotal connection with thepresser-lever, upon which the bell-crank is rocked to rai e and lower supported; i

s eeificatien of Letters Patent. Patented Oct. 16, 1917. ApplicationliledDecember12,1913; Seria1-No.8 Q6,142."'

the upper feed-dog, and secondly a pivotal connection with the upper feeddog carrier which, when the upper feed-dog rests upon the Worlqenables the upperfeedlifting eccentric to tilt-the bell-crank bodily upon the said carrier, and thus to rock the presserlever by which the bell-crank'is normally By the aforesaid means the work is engaged by upper and lower feeding members connected toa rocker in such manner that reciprocatory movements are simultaneously imparted to each 'member from a driving shaft :journaled below theworlcplate. vAnd .the upper member receives its rising-and falling movements from a bell-crank so connected with the presser-lever that said lever is rocked to elevate the presser-foot above the work during the effective work-advancing movemen'ts' of the feeding members and isppermitted tolower the foot upon the work during the ineffective movements of said feedlng'inembers.

- In theac'companying drawings, Figure 1 is'a' transverse sectional elevation of a sewing'machine embodying the improvements.

Fig. 2 is an end'elevation of the same, partly in sectlon. Fig. 3 1s a plan view of the same,

partly in section. Fig. 4 is an elevation of the upper and-lower feeding members, the presser-foot, and" their connections. is :1 side elevation of a modified form of the upper-feeddog and its carriershowing in dotted lines the position of the feed-clogs at the end of a feeding movement; and Fig.

'6 is a plan view of the same.

The present improvements are shown applied to'a machine constructed inaccord- 'an'ce with my'aforesaid patent, No. 932,272, the machine being provided with a base A, havingjournaled in suitable bearing members the longitudinally extending mainshaft '1 from which operative movements are imparted to the needle-bar 2, the looper 3, and the loop-spreader 4, said needle-bar Fig. 5

being mounted within the head of overing its rear end pivotally connected with upright'arms 10 carried by the feed-actuating rocking sleeve 11- fitted upon the longitudinal shaft 12, and maintained from enclwise movement thereonby the abutting adjacent ends of the split bushings 13. fitted within the bearing bosses 14 supported by the base A of the sewing machine frame, said split bushings being acljustably clamped within the'bearing bosses 14 by means, of set-screws :15, as shown in Fig. 3.

Secured upon the rocking sleeve 11 by means of clamping screw 16% is the split hub of a lateral arm 16 connected with the upper end of a link 17 whose lower end is adjustably secured by means 'of afbolt 18 to the slotted segmental arm 19 of-a rocker pivotally mounted upon a fixed fulcrum pin 20' and having a second arm 21 whose extremity is pivotally connected by-means of a pin 22 with one end of an eccentricrod 23 having at its opposite end a strap 24 embracing the feed-actuating eccentric 25 upon'the main-shaft 1.' It willbe seen that the length of the feeding movement is determined by the adjustment of the lower end of the link 17 with the slotted segmental arm 19.

The frame of the machine is provided with an upright bearing-plate 26 carrying the lateral fulcrum-stud 27 embraced by the boss 28 of the presser-lever 29 having secured to a suitable transverse seat in its forward end; by means of a fastening screw 30, the shank of the presser-foot 31, having the upturned forward portion 32 to the upper face of which is secured, by means of screws 33,'the shank of a chaining-off finger 34. The presser-lever is provided with 'a lateral arm 35, upon the upper face of which rests a pressure spring 36, said spring enter- 'ing a socket inthe' head of the bracket arm to meet the end of an adjusting screw 37,

' in the well knownmanner. The usual camlever 38 is mounted upon the bearing-plate 26 by means of the pivotal pin 39 and is adapted to engage the eccentric headof a screw-stud 40: carried by the press'er-lever 29 and provided with the lock-nut41.

. The" rocker 1011 which servesto-transmit reciprocating movements to the lower feed-dog 5 serves also to. impart reciprocating movements to thegupper feed-dog, and to this end the sleeve 11 of the rocker is provided with a lateral arm =oralever 42 having formed therein a slot 43 to receive a shoulderedstud 44 which serves to pivotally connect said arm withthe rearward end of-a linkbar 45. The link-bar may be adjusted with -respect to arm 42 of the rocker by loosening nut46, 'saidinut serving to confine the hub 48 of link-bar 45 between the headof stud 44 and a washer 47 The upper feed-dog 5* is pivotally connected-to link-bar 45 by means of screw 49 the upper portion of the feed-dog shank being connectcd by means of screw 50'to a carrier 51 provided with sleeve 52 pivotally mounted upon a stud 53 carried by the forwardly projecting arm 54 of a bell-crank 54, said stud 53 being secured in fixed position upon arm 54 by means of clamping nuts 55. v The carrier 51 is provided with a forwardly projecting foot 51 which is disposed adjacent the resser-foot, and the inner edge of said foot forms one of two guiding surfaces which abut opposite faces of the presser-foot shank, the second guiding surface being that side of the carrier into which the foot merges.

- Bell-crank 54 is fulcrumed uponpresserlever 29 by means of-screw 56, its arm 57 extending :below the work-plate and being connected by means of stud 58 with eccentric-rod 59 provided with fa strap 60 which embraces a lifting eccentric on the mainshaft 1. v

' In the operation of the machine, the rocker 10-1142, actuatedfrom eccentric 25, imparts reciprocatory movements simultaneously to each feed-dog, the carrier 51 rocking on stud 53 to permit the necessary movement of the upper feed-dog 5 Alternaterising and-falling movementsare imparted to; the upper feed-dog and to the presser-foot 31 from one eccentric on, a shaft journaled below the work-plate, the said presser-footbeing slightly elevated during the, advance of the work-feeding I members. and pressed upon-the work by -s rin 36 durin the return of said mem- P e l :3

bers to initial position. It will be seen that the feed-lifting eccentric for the upper feeddog serves, after a feeding movement, first to lower the pressure-lever 29, :whereupon fulcrum point 56 for the lifting bell-crank 54 becomes effective, and secondly to rock said bell-crank upon fulcrum 56 to liftthe carrier 51 and upper feed-dog, 5 simultaneously with the falling movement of the lower-feed-dog 5. through the action of-the feed-liftingeccentric' 9. By the aforesaid construction, a compact and eflicient machine is produced whichis simple in form and of .low' manufacturing cost. 7

-A modified form of the upper feed-dog and'its-carrier-is illustrated in: Figs. 5 and 6. The :upper feed-dog5 is'provided at each end with upwardly extending [spaced lugs 61 and .61 between which is pivoted by means of stud-screw 62 the lower .endof one of \two links-or swinging carrier 63, each link at its upper end being pivotally connected 'to-theupper arm ofthe bellcrank 1 The" link-bar 45 1 the feed-dog is connected to the latter at a point spacedfrom its connectlon with one ofthecarriers, as shown in Fig. 5. In

this instance a connecting stud-screw 62 passes through an aperture formed in the forward end of the link-bar and through similar apertures formed in .lugs 61 and 69 extending upwardly from the feed-dog. It will be seen that inthe foregoing modification the upper feed-clog is maintained in a horizontal plane .throughout its reciprocation and thus that the entiretoothed face of the dog remains in effective. engagement with the work during its feeding movement.

It will be understood that various changes may be made in the construction and arrangement of the parts without departing from the spirit of the invention, as manifestly the same is not limited to the. precise embodiment herein shown and described.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, the combination with a frame, a work-support, a driving shaft and stitch-forming mechanism operatively connected to said driving shaft, of an arcuately-movable presser-lever, a second lever fulcrumed upon said presser-lever, a feeding member movably supported by said second lever, and means operatively connected with the driving shaft for moving said second lever about its fulcrum and for imparting feed and return movements to said feeding member.

2. In. a sewing machine the combination with a frame, a work-plate and a driving shaft journaled in the frame below said work-plate, of stitch-forming mechanism operatively connected to said driving shaft, an arcuately-movable presser-lever, a bellcrank fulcrumed upon said lever and having one arm operatively connected to an actuating member on the driving shaft, a feeding member pivotally connected to said bell crank, a rock-lever operatively connected to the driving shaft, and a link-bar connected at one end to said rock-lever and at its opposite end to the feeding member.

3. In a sewing machine, the combination with a frame, a work-support, a driving shaft journaled in the frame, of stitch-forming mechanism, upper and lower feeding members, a rocker actuated by the driving shaft and adapted to impart simultaneous feeding movements to the feeding members, a presser-lever fulcrumed upon the frame, a presser-foot carried thereby, an element fulcrumed upon the presser-lever and connected to the upper feeding member, and an operative connection between said element and the driving shaft.

4. In a sewing machine, the combination with a frame, a work-plate, a driving shaft journaled in the frame below said workplate, an actuating member carried by said shaft of stitch-forming mechanism, upper and lower feeding members, a rocker actuated by-the driving shaft and adaptedv to impart simultaneous feeding vmovements to said feeding members, a presser-lever fulcrumed upon the frame, and a bell-crank fulcrumed upon the presser-lever and pivotally connected to the upperv feeding mem" her and having an arm extending below the work-plate and in operative relation with the actuating member on the driving shaft.

5. In a sewing machine, th combination with a frame, a work-plate, a driving shaft journaled in the frame below said workplate, an eccentric carried by said driving shaft, and feeding mechanism comprising upper and lower feed-clogs, of a rocker journaled below the work-plate and operatively connected to each feed-dog whereby reciprocatory movements are imparted thereto, an arcuatelymovab1e presserlever, a bell-crank fulcrumed upon said lever, an eccentric rod embracing the eccentric on the driving shaft and connected to one arm of said bell-crank, and a swinging carrier pivotally connected to the other arm of said bell-crank and to the upper feed-dog.

6. In a sewing machine, the combination with a frame, stitch-forming mechanism, a presser-lever fulcrumed upon said frame, a presser-foot, a feed-clog, a rock-lever, and a link-bar connecting said feed-dog and the roclolever, of a bell-crank fulcrumed upon said presser-lever, a carrier connected to the feeddog and provided with guiding surfaces abutting opposite faces of the presserfoot shank, a pivotal connection between the carrier and one arm of the bell-crank, and actuating means connected to the other arm of said bell-crank.

7 In a sewing machine, the combination with the work-plate, a driving shaft, opposed upper and lower feed-dogs disposed respectively above and below the work-plate, a feed-rocker operatively connected with the driving shaft, and a feed-bar sustaining the lower feed-dog and pivotally connected to said rocker, of a presser-lever having a fixed fulcrum, a presser-foot carried by said presser-lever, a rocking element fulcrumed upon said presser-lever and operatively connected with said shaft, a carrier pivotally sustained by said rocking element and upon which the upper feeddog is pivotally mounted, and a link-bar directly and pivotally attached to said rocker and said upper feeddog at a point spaced from the latters pivotal connection with the carrier.

8. In a sewing machine, the combination with a driving shaft, stitch-forming mechanism, a presser-lever and a fixed fulcrum therefor, a presser-foot, a feed-dog, a rocker, and a link-bar connecting said feed-clog and the rocker, of a rocking element fulcrumed upon said Presser-lever, a supporting mem Copies of this patent may be obtained for ber sustained in fixed position upon said rocking element, spaced links fulcrumed upon said supporting member, pivotal connections between said links and the feed-dog, and actuating means for said rocking element.

9. In asewing machine, the combination with a driving shaft, stitch-forming mech anism, a presser-lever and a fixed fulcrum therefor, a presser-foot, a feed-dog, a rocker and a link-bar connecting said feed-dog and the'rocker, of a rocking element fulcrumed upon said presser-lever, a supporting member, means including an eccentric stud for the feed-dog, and actuating means for said rocking element.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing'witnesses. Y

ALFRED GRIEB. Witnesses W. Lnn HELMS, LEONARD E. FIscHER.

five cents each, by addressing the Commissioner of Patents. Washington, D. G. 

